A level sensing device with a high frequency radar system is provided. The radar system includes a radar high frequency module, a carrier board and a controller. The radar high frequency module is mounted on the carrier board using surface mount techniques. The controller includes a processor and the radar high frequency module has a plurality of components including one or more microwave integrated circuits, a radiating patch antenna, and coupling means for channeling a radiated signal from the patch antenna out of the module. The components are encapsulated to form the module and the coupling means includes a dielectric rod.
|
5. A method of operating a level sensing device, comprising:
providing a high frequency radar system with a high frequency radar module, a carrier board and a controller with a processor,
mounting the module on the carrier board,
encapsulating high frequency radar module components to form the module,
operating the high frequency radar system in a millimeter band,
transmitting a radiated signal caused by a controller of the high frequency radar system towards a target material,
receiving a return radar signal in the radar system, and
determining a level of the target material by processing the return radar signal.
1. A level sensing device, comprising:
a high frequency radar system, the radar system including
a radar high frequency module,
a carrier board, and
a controller with a processor,
wherein the radar high frequency module is mounted on the carrier board using surface mount techniques, the radar high frequency module comprising
a plurality of components including one or more monolithic microwave integrated circuits (MM1Cs) packaged as bare die,
a radiating patch antenna, and
a dielectric rod for channelling a radiated signal from the patch antenna out of the module,
wherein the plurality of components, the patch antenna and the dielectric rod are encapsulated to form the module.
2. The device according to
3. The device according to
a target material, and
a container, wherein the target material is in the container, and wherein the controller causes a radiated signal to be channelled toward the target material.
6. The method according to
a plurality of components including one or more monolithic microwave integrated circuits (MMICs),
a radiating patch antenna, and
a dielectric rod for channelling a radiated signal from the patch antenna out of the module.
7. The method according to
screening the module components, wherein the components are encapsulated with a material which provides screening of the components.
9. The method according to
providing a container, wherein the target material is located in the container,
extracting, from a store, information relating to the target material and the container by the processor, and
deriving an approximate volume of the material in the container by the processor.
|
This application is the US National Stage of International Application No. PCT/GB2008/050161 filed Mar. 7, 2008 and claims the benefit thereof. The International Application claims the benefits of Great Britain Application No. 0705449.7 GB filed Mar. 22, 2007; both of the applications are incorporated by reference herein in their entirety.
This invention relates to a level sensing device using a high frequency radar system, in particular for range finding and level sensing of bulk materials, or fluids.
For radars operating at high frequencies (HF) using monolithic microwave integrated circuits (MMICs) packaged as bare die, construction costs have traditionally been high. In addition, the transition to the antenna has required complex precision construction and the MMICs are delicate components requiring protection which further complicates the issue of manufacture. Conventionally, modules with the MMICs mounted onto them are connected to carrier circuit boards using bond wires or soldered wire links. The complete assembly then has to be protected in a housing. Antenna connections are frequently made using precision transitions to waveguide, which can be time consuming and expensive to manufacture. Furthermore, for level sensing, the size of aperture available to operate the radar through is limited and at conventional frequencies this can lead to poor resolution. However, increasing the frequency of operation leads to higher costs for components and manufacturing. In addition, level sensing, or range finding to determine quantities of bulk materials, particularly powdered materials, such as cement or flour, takes place in an environment which is hostile for electronic components. Fluid level monitoring may take place in remote situations, where maintenance is difficult, so a reliable device is particularly important.
In accordance with a first aspect of the present invention, a level sensing device comprises a high frequency radar system, the system comprising a radar high frequency module, a carrier board and a controller; wherein the radar high frequency module is mounted on the carrier board using surface mount techniques; wherein the controller comprises a processor; wherein, the radar high frequency module comprises a plurality of components including one or more monolithic microwave integrated circuits (MMICs) packaged as bare die, a radiating patch antenna, and coupling means for channelling a radiated signal from the patch antenna out of the module, wherein the radar high frequency module components are encapsulated to form the module; and, wherein the coupling means comprises a dielectric rod.
The present invention addresses the problems caused by the physical environment in which the level sensing device must operate, by providing a compact, well protected package, using a dielectric rod, rather than a traditional antenna and complicated waveguide transitions.
The system can operate over a wide frequency range, but preferably, the radar system operates in the millimeter band.
This gives improved resolution and higher gain for a given available aperture size.
Typically, the operating frequency is between 40 and 120 GHz, more typically in the region of about 75 to 85 GHz.
This frequency range gives particularly good results for returns off dry or dusty materials.
Preferably, the components are encapsulated with a material which provides screening of the microwave components.
The packaging provides both physical protection from the environment, and protection from electrical interference. Providing both a screening and a protective function in the same part is convenient and saves in manufacturing costs.
Preferably, the controller causes a radiated signal to be channelled toward a target material; wherein a return radar signal is received in the radar system; and wherein the processor processes the return signal to determine a level of the target material.
This can be used on any type of target material to determine its level at the point to which the signal is directed.
The invention can be used for determining levels of fluids or bulk products in open environments, such as rivers or gravel yards, but in one embodiment, the target material is in a container.
The return signal can be used in combination with a known total height of the container to determine where the level of the material is.
Preferably, the processor extracts from a store, information relating to the target material and the container, and derives an approximate volume of the material in the container.
This can be helpful to determine how soon a silo e.g. on a production line for concrete structures, needs to be refilled based on the amount of material remaining and likely rate of use.
The level sensor may be used on many different objects, but typically, the target material comprises a fluid or bulk product, for example concrete, flour, grain or oil. Alternatively, in open air situations, the fluid may be water, such as reservoir levels, or waste products, such as in sewage treatment.
An example of a level sensing device using a high frequency radar system according to the present invention will now be described with reference to the accompanying drawings in which:
The present invention solves the construction problems of the conventional device by packaging the MMICs in a module 28 that can be used as a component in standard printed circuit board assembly. This is shown in
An example of an application of the system of the present invention is shown in
To measure the level of material within a container, the radar system emits radiation at a suitable frequency and the returns are processed in conjunction with known information about the overall height and volume of the container. Level sensing may be used as part of a process for controlling manufacture, so that the amount of material used up, or remaining in the silo 31 can be determined and appropriate top ups built into the production process to minimise downtime. Since filling and emptying of the silos is usually done through vents 37, 38 aligned along the axis, the position of the level sensing device can be offset to one side, or other of the central axis in the silo to obtain a more accurate estimate, as illustrated in
Another example of level sensing is in its application to measuring fluid levels in open environments. Examples of this include measuring height of water in a river or reservoir, or wave height beneath oil rigs, so that advance warning can be given of potentially dangerous situations.
The present invention reduces the cost of manufacturing a system for operation at high frequencies by encapsulating all RF components in a single screened module, which can be incorporated into a manufactured item using production line surface mount techniques, rather than hand assembly and reduces the overall number of passes for each of the manufacturing steps. The components themselves may still be relatively expensive, but the modular structure allows a simple production facility to produce the radar systems without changing their equipment by buying in the modules. These can be made in a clean room by a company specialising in that type of manufacture, but the company producing the finished product does not need to invest in this type of facility.
The use of a dielectric rod to extract the radiation from the encapsulated package is a further simplification, in contrast to the use of waveguide transitions which are very complex to manufacture.
Unlike the conventional manufacturing process whereby a module was laid onto a carrier circuit board and bonded, then covered over for protection and other components were soldered onto the board in their positions afterwards, the present invention allows most of the assembly to be done in factories which do not have a clean room and the high frequency radar module is manufactured off-site by specialist, then incorporated as part of an assembly line.
Sherry, David, Garrod, Adrian George, Moore, Katherine
Patent | Priority | Assignee | Title |
10001558, | Jul 08 2013 | VEGA Grieshaber KG | Determining a level and flow speed of a medium |
11499861, | Feb 18 2019 | VEGA Grieshaber KG | Radar module |
9551606, | Jul 08 2013 | VEGA Grieshaber KG | Determining a level and flow speed of a medium |
9677922, | Jul 08 2013 | VEGA Grieshaber KG | Universal measurement data acquisition in water |
9683882, | Jun 30 2014 | KROHNE Messtechnik GmbH | Microwave module |
9945709, | Jul 08 2013 | VEGA Grieshaber KG | Determining a distance and a flow speed of a medium |
Patent | Priority | Assignee | Title |
5546088, | Oct 06 1993 | LFK-Lenkflugkorpersysteme GmbH | High-precision radar range finder |
6014100, | Feb 27 1998 | VEGA Grieshaber KG | Two-wire RADAR sensor with intermittently operating circuitry components |
6028560, | Nov 05 1997 | Robert Bosch GmbH | Device for directional transmission and/or receiving of electromagnetic waves |
6191724, | Jan 28 1999 | MCEWAN TECHNOLOGIES, LLC A NEVADA CORPORATION | Short pulse microwave transceiver |
6366245, | Dec 21 1998 | Robert Bosch GmbH | Device for directionally emitting and/or receiving electromagnetic radiation |
6927734, | Sep 27 2002 | Siemens Aktiengesellschaft | Dielectric rod antenna |
7068213, | May 13 2000 | ENDRESS & HAUSER GMBH & CO KG | Level meter |
7075480, | Apr 10 2002 | VEGA Grieshaber KG | Level measurement device having electronics and antenna in one housing |
7173436, | Nov 24 2004 | Rosemount Tank Radar AB | Antenna device for level gauging |
7233278, | Sep 10 2004 | Rosemount Tank Radar AB | Radar level gauge with switch for selecting transmitter or receiver mode |
7586450, | Dec 06 2004 | ENDRESS + HAUSER GMBH + CO KG | Device for transmitting and/or receiving high-frequency signals in an open or closed space system |
7924216, | Apr 30 2008 | Rosemount Tank Radar AB | Method of determining a disturbance echo profile for a radar level gauge system |
7924217, | Jun 03 2008 | Rosemount Tank Radar AB | High sensitivity frequency modulated radar level gauge system |
8040274, | Jul 03 2006 | ENDRESS + HAUSER GMBH + CO KG | Apparatus for determining and/or monitoring the level of a medium |
8085187, | Jan 27 2009 | Magnetrol International, Incorporated | Through air radar sensor |
20040056667, | |||
20050035901, | |||
20050093738, | |||
20050225480, | |||
20050280573, | |||
20070139256, | |||
20070200749, | |||
20100052974, | |||
20100060512, | |||
20100090883, | |||
20100103024, | |||
20110140951, | |||
EP2219045, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Mar 07 2008 | Siemens Aktiengesellschaft | (assignment on the face of the patent) | / | |||
Sep 07 2009 | GARROD, ADRIAN GEORGE | SIEMENS MILLTRONICS PROCESS INSTRUMENTS, INC | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 023224 | /0025 | |
Jul 01 2010 | SIEMENS MILLTRONICS PROCESS INSTRUMENTS, INC | Siemens Canada Limited | CERTIFICATE AND ARTICLES OF AMALGAMATION | 027531 | /0173 | |
Nov 08 2011 | Siemens Canada Limited | Siemens Aktiengesellschaft | ASSIGNMENT OF ASSIGNORS INTEREST SEE DOCUMENT FOR DETAILS | 027557 | /0304 |
Date | Maintenance Fee Events |
Oct 13 2015 | M1551: Payment of Maintenance Fee, 4th Year, Large Entity. |
Oct 07 2019 | M1552: Payment of Maintenance Fee, 8th Year, Large Entity. |
Oct 11 2023 | M1553: Payment of Maintenance Fee, 12th Year, Large Entity. |
Date | Maintenance Schedule |
May 22 2015 | 4 years fee payment window open |
Nov 22 2015 | 6 months grace period start (w surcharge) |
May 22 2016 | patent expiry (for year 4) |
May 22 2018 | 2 years to revive unintentionally abandoned end. (for year 4) |
May 22 2019 | 8 years fee payment window open |
Nov 22 2019 | 6 months grace period start (w surcharge) |
May 22 2020 | patent expiry (for year 8) |
May 22 2022 | 2 years to revive unintentionally abandoned end. (for year 8) |
May 22 2023 | 12 years fee payment window open |
Nov 22 2023 | 6 months grace period start (w surcharge) |
May 22 2024 | patent expiry (for year 12) |
May 22 2026 | 2 years to revive unintentionally abandoned end. (for year 12) |